Effect of Feeding Adaptation of Italian Simmental Cows before Summer Grazing on Animal Behavior and Milk Characteristics

摘要

The traditional transhumant system of rearing dairy cows in mountain areas expects animals to remain indoors in the valley during the cold season, whereas during the summer they are moved to pastures at progressively higher altitudes. The animals transferred from the valley farm to the alpine pasture must adapt to various management changes. This study aimed to evaluate whether a gradual inclusion of fresh grass in the diet of dairy cows in the valley farm can improve the performance and milk characteristics during summer grazing. Three groups of six animals each were considered: one group was kept in the stable, one was transferred from the valley to the summer farm without adaptation, and the other was progressively adapted to grazing with a feeding adaptation period. Compared to animals kept indoors, grazing animals had similar performance and milk characteristics, higher rumination time and, with respect to volatile compounds in milk, higher concentrations of alcohols, aldehydes, hydrocarbons, and ketones but lower concentrations of organic acids, phenolic compounds, and dimethyl sulfone, regardless of the feeding adaptation. In conclusion, the gradual inclusion of fresh grass in the diet in the valley farm did not improve the performance and milk characteristics during summer grazing.